%% Saturn
warning off
clc;clear;close all

format longg
options_negx = odeset('RelTol',1e-13,'AbsTol',1e-13,'Events',@NegXcrossing);
options=odeset('RelTol',1e-13,'AbsTol',1e-13);
options_fmincon = optimoptions('fmincon', 'MaxFunctionEvaluations', 5000, ...
    'MaxIterations', 5000,'ConstraintTolerance',1e-6,'Algorithm','Interior-point','stepTolerance',1e-21);
%% Inputs.
G           = 6.674e-11 * ((1/1000)^3); % Gravitational parameters

mass_central = 1.989e30;
%[] Mass of central planet

mass_moon = 5.972e24;         %Callisto
%[] mass of moons

DU = 151.73e6;           %Callisto
%[km] Semi-major axis of Moons, used as distance units for each CRTBP
%environment.

moonName = {'Luna'};
%[] Name of the Moons

thetao = 0;
%[] Initial position of the moon relative to the first point of aries

GM_central = mass_central*G;
%[] Gravitational parameters

GM_moon = mass_moon*G;
%[] Gravitational parameters

N = length(mass_moon);
%[] Number of Moons

u = zeros(N,1);
for ii = 1:N
    u(ii) = GM_moon(ii)/(GM_moon(ii)+GM_central);
end
%[] Gravataional ratio

TU = zeros(N,1);
VU = zeros(N,1);
for ii = 1:N
    TU(ii) = sqrt(DU(ii)^3/GM_central);
    VU(ii) = DU(ii)/TU(ii);
end
%[] Time constant for each crtbp system

theta_dot = zeros(1,N);
for ii = 1:length(theta_dot)
    theta_dot(ii) = sqrt(GM_central*DU(ii))/DU(ii)^2;
end
%[] Theta dot for each planet.


% planetNumb = 1;
% [L1,L2,L3,L4,L5] = librationPoints(u(planetNumb));
% L_ = [L1,L2,L3,L4,L5];
% for ii = 1:length(L_)
%     L_pos = L_(:,ii);
%     J_L(ii) = jacobiConst(L_pos,zeros(3,1),u(planetNumb));
% end

%% environment settings
dt = 0.01;
startphase=0; % changing the starting position of the periodic
% orbit to show changes in the pole visibility based on the Satellite's position wrt the Sun's pole
% OpenCRTBP_u(u)
%% Define inertial frame FNs
[xs,ys,zs] = ellipsoid(-0,0,0,696340,696340,696340,180);
figure;
s = surface(xs,ys,zs);
rotate(s, [1 0 0], 7.25);
rotate(s, [0 0 1], 73.67+0.014*(2023-1850));
InclinationRotationAngle = 7.25;
RAANRotationAngle = 73.67+0.014*(2023-1850);
PoleDirection = Rotation([0;0;1],RAANRotationAngle,'Degrees')*...
    Rotation([1;0;0],InclinationRotationAngle,'Degrees')*...
    [0;0;1];
rotate(s, PoleDirection, -70);
FN_i = s.VertexNormals;
[row,col,~] = size(FN_i);
%%
load('SEL1_Lyapunov.mat');
size = 1;
[t,S] = ode113(@(t,S)CR3BP_n(t,S,u),[0:dt:2*pi],IC(:,size),options);
S=S';
S_i = zeros(6,length(t));
for ii = 1:length(t)
    S_i(:,ii) = C2I_primary(S(:,ii),u,DU,VU,t(ii));
    epoch(ii) = datetime(2023,1,1,0,0,0) + seconds(t(ii)*TU);
end
L1.S_i = S_i;
L1.epoch = epoch;

%% Simulation paramters %%

%%
% IC_L4 = IC_L4_VL(:,ind_opt);
% T_L4 = 2*pi;
% dt = 0.01;
%
% OpenCRTBP_u(u); hold on
% L4= DetermineOptimalL4andL5State(IC_L4,T_L4,u,DU,VU,TU,dt);
% We not have the states of the optimally placed L4 in SCI frame.

%% Given orbital states of the satellite (varying inclination), allowable theta_max, and target latitude,
%  Determine visibility

CameraAngleCapability=[70,60,50,40];
target_latitude = -90:90;
orbit_amount = 3;
%%
for iii = 1:length(CameraAngleCapability)
    iii
    ind = 1;
    visibility=zeros(row,col);
    parfor ii = 1:row
        for jj = 1:col
            normvec = [FN_i(ii,jj,1);...
                FN_i(ii,jj,2);...
                FN_i(ii,jj,3)];
            for k = 1:length(L1.epoch)
                posvec = L1.S_i(1:3,k);
                angle_temp = acosd(dot(normvec,posvec)/(norm(normvec)*norm(posvec)));
                if angle_temp < CameraAngleCapability(iii)
                    visibility(ii,jj) = visibility(ii,jj)+1;
                end
            end
        end
    end
    % Calculate the averaged visible-day for each target-Latitude.
    % get index, which depends on the mesh size.
    for p = 1:length(target_latitude)
        Average_visibility{iii}(ind,p) = (sum(visibility(p,:))/180)*dt*TU/3600/24;
    end
    ind = ind + 1;
end


%%
figure; hold on     
% markers = {'+','pentagram','o','square'};
linecolors={'k','r','g','b'};

for ii = 1:4
    plot(Average_visibility{ii},target_latitude,'Color',linecolors{ii})

end
ylabel('Heliographic Latitude [deg]','Interpreter','latex')
xlabel('Mean Visibility Duration [Days/year]','Interpreter','latex')
set(gca,'FontSize',12)
legend('\Theta_{max}=70^\circ','\Theta_{max}=60^\circ','\Theta_{max}=50^\circ','\Theta_{max}=40^\circ')
findfigs
ylim([-90,90])
yticks(-90:30:90)
%%
